Apparatus for producing stereoscopic effects in motion pictures



Feb. 7, 1939. A. ADAMS ET AL APPARATUS FOR PRODUCING STEREOSCOPIC EFFECTS IN MOTION PICTURES 4 Sheets-Sheet l Filed .Aug. 5, 1956 [A /5N T020: 19.42040 ,4. 9019mm Em. EH 0. Lamaze);

flrroez sx Feb. 7, 19.39.- H. A. ADAMS ET AL 2,146,135

APPARATUS FOR PRODUCING STEREOSGOPIC EFFECTS IN MOTION PICTURES Filed Aug. 3, 1936 4 Sheets-Sheet 3 ,4 Tree/v5.1

Feb. 7,- 1939. H. A. ADAMS El AL I 2,146,135

APPARATUS FOR PRODUCING STEREOSCOPIC EFFECTS IN MOTION PICTURES Filed Aug. 3, 1956 4 Sheets-Sheet 4 ag IV/ 7 /I2//6$ //64 Patented Feb. 7, 1939 UNITED STATES APPARATUS FOR PRODUCING STEREO- SCOPIC EFFECTS IN MOTION PICTURES Hal-om A. Adams, Bakersfield, and Lemert, Los Angeles, Calif.

Ralph D.

Application August 3, 1938, Serial N0. 93,976

3 Claims. (Cl. 88-165) Our invention relates to the art of producing ,motion pictures, and relates in particular to an apparatus for producing in motion pictures the appearance of depth, ordinarily referred to as stereoscopic effects.

It is an object of the invention to provide .an apparatus for producing motion pictures,

wherein the light rays passing from a scene or object are subjected to different conditions of refraction during the exposure of consecutive frames of a motion picture film, the result being that the optical axis of the camera is shifted back and forth in timed relation to the bringing of consecutive frames of the motion picture film into focal position relative to the camera lens.

It is a further object of the invention to provide an apparatus for producing motion pictures, wherein refracting means are employed to inter- 'mittently and alternately offset the optical axis of the lens system of a motion picture camera, with the result that adjacent frames of a motion picture film photographed in such camera have thereto. The invention also includes means whereby these images are subsequently rectified, or brought into alignment prior to the viewing thereof, so that the image will not appear to jump back and forth in the vision of the viewer. The shifting of the images carried in consecutive frames of a positive film may be accomplished in the projection of such images onto a screen, or in the printing of a positive film from a negative having images in staggered relation the images may be moved into longitudinal alignment on the motion picture film which is to be v used .for projection purposes.

It is a further object of the invention to provide an apparatus for producing motion pictures, wherein a refracting member, such as an optical flat lens, is disposed in a position crossing the optical axis of the lens of a camera, and during the taking of a motion picture is swung through an angle relative to the optical axis of the lens in a timed relation to the step-by-step advancing movement of the film relative to the lens of the camera. In the preferred practice of the invention the refracting member is disposed in a position normal to the optical axis of the lens during the exposure of one frame of the motion picture film, is swung to the right during the exposure of the first succeeding frame, is returned to normal position during the exposure of the second succeeding frame, and is then swung to the,

left during the exposure of the third succeeding frame, this cycle being repeated as the exposure of consecutiveframes of the motion picture film proceeds.

member in a position crossing the optical axis of the camera lens, together with means for swinging the refracting member in timed relation to the operation of the film moving mechanism and therefore in timed relation to the advancing movement of the film through the camera.

It is a further object of the invention to provide an attachment incorporating the foregoing features, which may be readily secured to the exterior of a standard motion picture camera.

It is a further object of the invention to provide a motion picture camera having a refracting member disposed in a position crossing the optical axis of the camera lens and having adjustable means for swinging the refracting member in timed relation to the movement of the motion picture film in the camera, so that the refraction of the light rays passing from the image or object to the motion picture .film in focal position relative to the. lensmay be refracted in accordance with conditions under which the motion picture is being taken.

Further objects and advantages of the invention will be made evident throughout the following part of the specification.

Referring to the drawings, which are for illustrative purposes only,

Fig. 1 is, an elevational view of a camera equipped with a mechanism for the practice of our invention.

Fig. 2 is a plan view corresponding to Fig. 1.

Fig. 3 is a. diagrammatic view showing essential elements of the invention and indicating the results obtained by partial rotation of a refracting member.

Fig. 4 is a view of a portion of motion picture film photographed in accordance with the principles explained relative to Fig. 3.

Fig. 5 is. a view of a portion of motion picture film on which the consecutive images have been rectified or aligned.

Fig. 6 is an enlarged, partly sectioned view taken as indicated by the line 6-6 of Fig. 2.

Fig. 7 is an enlarged, fragmentary, cross-sectional view taken on a plane indicated by the line 1-1 of Fig. 1.

Fig. 8 is a sectional view taken on a plane indi cated by the line 8-8 of Fig. 6.

Fig. 9 is an enlarged plan view of the refracting means, with the cover plate of the casing thereof removed.

Fig. 10 isa fragmentary section taken as indicated by the line Ill-i8 of Fig. 9.

Fig. 11 is a fragmentary section taken as indicated by the line I of Fig. 9.

Fig. 12 is a bottom plan view of the refracting device shown to enlarged scale in Fig. 9, with the bottom cover plate removed therefrom.

Fig. 13 is a bottom plan view similar to Fig. 12, but showing the parts of the mechanism in diflerent positions from the positions thereof disclosed in Fig. 12. a

Fig. 14 is a perspective view of 1 the locking plate employed to lock the lever of the refracting means.

In Figs. 1 and 2, which are schematic in character, we show a camera 20 of a well known form having a base structure 2| secured to a tripod 22.

The base structure 2| carries a turret 23 havin an objective lens 24, and mounted on the base structure 2| rearwardly oi the turret 23 is a casing 25 which is laterally slidable relative to the turret 23 so that a film advancing mechanism within the casing 25, or a range finder or focusing device, also within the casing 25, may be brought into alignment with the optical axis of the lens 24.

A casing 26 is secured in a plane in front of the lens 24 by a support 21 which is connected to the base 2| of the camera, this casing 28 including a refracting means and actuating means therefor, the characteristics of which will be readily understood from the following explanation of Fig. 3. In Fig. 3 we show an image or object 28 from which a light image is projected as indicated by lines 29 through the objective lens 24 of the camera '20 to a focal plane :v-y, wherein a negative motion picture film 3| is exposed to the light image. The optical axis of the lens 24- is indicated by a line 32 which likewise represents the path of light rays from a center point 33 of the object 28 to a center point 33' of the exposed area on the film 3|. In a position crossing the optical axis 32, preferably between the lens 24 and the object 28, we place a refracting member 34, which, in the preferred practice of the invention, consists of an optical flat glass disposed in the casing 26,

In Fig. 4 we show a portion of the film 3| having frames A, B, C, D, and E produced in the customary manner by exposing portions of the film 50 3| in consecutive order before the lens 24, in

timed relation to the operation of a shutter mechanism forming an ordinary part of the camera assembly: When a frame of the film 3|, such as the frame A, is exposed in the focal position 55 indicated by the line a:-y of Fig. 3, the refracting means 34 may be disposed in an initial or primary position, such as a position normal to the optical axis 32. Accordingly, there will be no refraction of light rays passing from the object 28 to the film 3|, and the image of the point 33 will be transmitted along the optical axis 32 to the point 33' of the frame A. Accordingly, an image of the point 33 will appear in the center of the frame A at (1.. During the movement of the film 3| to .65 bring the frame B into focal position, the retion of the optical axis 32 will now extend for- 'wardly from therefra'cting member 34 as indicated by' the dotted line 32a. The center point 33' of the focalplane :c-y will now receive light 75 which passes from the object 28 along the line indicated at b in the frame B of the film 3|.

3241, and the center point 33 of the object 28 will be recorded to one side of a center line LL as The film 3| is then advanced to the frame C, and during its advancing-movement the refracting member 34 is returned to its intermediate or non refracting position in which it is shown in full lines in Fig. 3. Accordingly, the center point 33 of the object 28 will appear in the center of the frame C as indicated at cm Fig. 4. While the 'film 3| is being advanced to the frame D, the

refracting member 34v is swung leftwardly into the position in which it is indicated in Fig. 3 in dotted lines 38. In this position 38 the refracting member 34 will offset the optical axis 32 at 39 I so that the forward portion of the optical axis will extend forwardly from the refracting member, as indicated by the broken line 32b, this causing the image of the point 33 of. the object 28 to be offset as indicated at d in the frame D in a direction opposite to the offset of the center point at b in frame B. The cycle of operations of the refracting member 34, as explained relative to frames A to D inclusive of the film .3|, is then repeated in conjunction with the exposure of the next four frames of the film 3|, starting with the frame E wherein the center point 33 starts again at the centralized position a indicated in the frame E. The action of the refracting means 34 in shifting the paths along which light rays may pass from the object 28 to the focal plane x-y, forexample, from the rectilinear forward portion 32' of the optical axis 32 to the offset portions 32a and 32b, has the effect of viewing the image in consecutive. frames of the motion picture film first along a central axis, then from one side, then again from the central axis, and finally from the opposite side of the central axis. Assuming that the object 28 is stationary, the side images b and at will be different from each other and from the centralized images a and c.

A positive film 4|, Fig. 5, may be prepared from the negative film 3|, and in order to prevent the images from jumping back and forth in the vision of the viewer, the laterally offset images are rectified-or centralized so that the center points of all of the images of the consecutive frames will lie on the longitudinal line LL. Accordingly, the respective images of the center point 33, Fig. 3, which appear at a, b, c, and d, in Fig. 4, will now appear in the positions indicated by a, b, c, and d in the positive film 4| so that when the respective frames are viewed in a viewing device orare viewed by projecting them into a screen, the motion picture image will stand steady upon the screen.

As best shown in Figs. 6, 7, and 9, the casing 26 has an upper chamber 42 defined by front and rear walls 43 and 44 and side walls 45. The

v upper wall of the chamber 42 consists of a removable cover plate 46, Fig. 9 showing the chamber 42 with the cover plate removed therefrom. The refractory member 34 is mounted in a circular holder '41 secured to the upper end of a shaft 48 which projects through a bearing 49 carried in the lower wall 5| of the chamber 42, in the manner best shown in Fig. 7. The holder 41 supports the refracting member 34 on the optical axis of the lens 24, and windows of glass 52 and 52a are provided in the front and rear walls 43 and 44 of the chamber 42 through which the light image from the object may pass to the lens and then to the focal plane of such lens. As indicated in Fig. 1 by dotted lines 53, a sun shade may be secured to the front wall 43 of the chamber 42.

To swing the retracting member 34 from its intermediate position to the rightward and leftward positions thereof indicated by dotted lines 96 and 98 in Figs. 3 and 9, a lever 54 is connected to the lower end 55 of the shaft 48, this lever extending within a lower chamber 56 of the cas ing 26, which chamber 55 projects forwardly in a plane disposed below the lower wall 5| of the chamber 42. The lever 54 is swung through positions corresponding to the desired positions of the refracting member 84 by means of a cam mechanism 51 shown in Figs. 7, 12, and 13. This cam mechanism 51 includes a shaft 58, the upper portion of which is carried in a bearing 59 supported in the lower wall 5I of the chamber 42, and the lower end of which is carried in a bearing 6| supported in vertical alignment with the bearing 59 by means of a bracket 52 which, as best shown in Fig. 13, is secured by means of screws 59 to the lower face of the wall 5|. The shaft 58 carries a primary cam 64 and a secondary cam 65. The primary cam 64 has diametrically opposed, intermediate lobes 65 and 51, a high lobe 58 disposed between the lobes 65 and 51, and a low lobe 69 diametrically opposed to the high lobe 68. A cam follower guide member 1|, is secured tothe wall 5| by means of screws 12. This guide member 1| has an opening 18 radially aligned with the primary cam 64 in which a cam follower 14 is slidable, so that the front rounded end 15 thereof will ride over the lobes 56 to 59 inclusive of the primary cam 54 as such cam is rotated. The rearward end of the cam follower 14 has a. chamber 16, as shown in Fig. 12, in which a spring 11 forces an engagement member 18 outwardly so that it will normally engage a shoulder 19 formed at the rearward end of the chamber 16. The engagement member 18 of the cam follower 14 engages the forward end 8| of a lever 82 which is fulcrumed on a pivot means 83 so as to swing in a substantially horizontal plane from the position in which it is shown in full lines to the angular position in which it is shown in Fig. 13. The rearward end 84 of the lever 82 is connected by a link 85 with the other end 86 of the lever 54 which is connected to the vertical shaft 48 for the purpose of supporting and swinging the refracting member 84. For the purpose of adjustment of the length of the link 85, it includes aturnbuckle type screw 81.

When either intermediate lobe 55 or 51 of the cam 54 is in engagement with the cam follower 14, the lever 82, the lever arm 54, and the refracting member 34 will be in intermediate position, as shown in Fig. 12. As shown in Fig. 13, when the cam follower 14 is respectively in engagement with the low and high lobes 69 and 58, the levers 82 and 54 and the refracting member 34 will be in their rightward and leftward positions. In Fig. 13 the lever members 82 and 54 are shown in their rightward positions; that is, they are in such positions that the refracting member 34 will be held in the rightward position shown in dotted lines 36 in Figs. 3 and 9. Since the cam 54 has four lobes of the character previously described, one complete revolution thereof produces a complete cycle of movement of the retracting member 34 from intermediate position to rightward position, back to intermediate position, and then to leftward position.

Locking means 88 are provided for holding the retracting member 34 from vibration during the time it is in its intermediate, rightward, and leftward positions- This locking means 88 we have incorporated withthe lever arm 54. It includes a block 89, such as shown in perspective in Fig. 14, having an arcuate and conical wall 9| formed with grooves or serrations 92. As shown in Figs.

7,12, and 13, this block 89 is held by guides or gibs 93 in a position against the lower face of the wall 5| and so as to'slide radially relative to the axis of the shaft 48. As shown in Fig. 7, the

block 89 is disposed above the rightward or outer end 85 of the lever 54 and is adapted to have a reciprocating movement in radial direction limited by a pin 94 which projects downwardly from the wall 5| into a slot 95 in the block 89. A spring 95 is secured by means of a support 91 in such position that it will press the block 89 radially inwardly toward the shaft 48. The lever 54 is shown with a squared hole 98 through which a pin 99 of square cross section projects, this pin having a knife edge IOI formed on the upper end thereof for engagement with the grooves or serrations 92 of the block when the block 89 is moved inwardly from the position in which it is shown in Figs. '7 and 12 to the position thereof shown in Fig, 13. The pin 99 is resiliently supported on a spring I02 sothat it may'move downwardly when the block 98 engages the knife edge I0|. formed at the upper end thereof.

\Between the block 89 and the secondary cam 65 a V-shaped yoke I04 is pivoted on a screw I05 which threads upwardly into the wall 5|. This yoke .I04 has a cam follower I06 at the forward end thereof for engaging the secondary .cam 55 and has a circular formation I01 at the opposite end thereof for engagement with the forward edge of the block 89. The cam 65 has four lobes I08 disposed at angles of and being,

of'such character that during the time the cam follower 14 is moving inwardly and outwardly, and likewise during the time that the arm 54 is swinging; the cam follower I06 will be forced rightwardly as shown in Fig. 12, so that the block 89 will be forced rightwardly against the pressure of the spring 95. During the times the lever 54 is to remain stationary, the cam follower I06 moves leftwardly into a space between two adjacent lobes I08 of the cam 65, as shown in Fig. 13, permitting the yoke I04 to rotate leftwardly so that leftward movement of the formation I01 at the rightward end of the yoke I04 will permit the block 89 to be moved leftwardly by the spring so as to carry a serration 92 of the block 89 into engagement with the pin 99. Should there be any unevenness in the faces of the cam lobes 65, 61, 58, and 69 of the primary cam 54, the motion thereby transmitted to the cam follower 14 will be absorbed by the spring 11, since the lever 82 is at this time held immovable by reason of its connection, to the locked lever 54.

The cams 64 and 65 are driven by, and in synchrony with, the drive mechanism of the camera 20 by use of the following parts. As

shown in Fig. 7, a bevel gear I09, connected to the upper end of the shaft 58, is engaged by a bevel pinion II I which is secured to the inner end of a shaft H2 which projects through the leftward side wall 45 of the chamber 42 at a point A cover member 5 may be end II8 'thereof projects into a gear case II9 formed as a part of an adaptor I2I, which is insertable between the camera motor I22 and the motor support I23 of the camera 20. As shown in Fig. 6, this adaptor I2Iv has a main casing I24 equipped with a flange I25 adapted to engage the outer face I26 of the motor support I23, and a flange I21 against which the flange I28 of the motor I22 may be secured. By means of bearings I29 and I3I, the main casing I24 carries an extension shaft I32, the inner end I33 of which connects to the driven shaft I34 of the usual mechanism for intermittently moving the film in the camera, the outer end I35 of the shaft I32 being so formed that it will engage the shaft of the motor I22. The shaft I32 has a screw or worm I36 thereon which engages a worm wheel I31 mounted, as shown in Figs. 6 and 8, on av shaft I38 which projects forwardly from the main casing I24 of the adaptor I 2I througha tubular extension I39 into the gear case II9 wherein a bevel pinion MI is secured to the end of the shaft I38 so as to engage a bevel gear I42. The bevel gear I42 has a bore I43 through which the shaft II2 may slide, and is provided with a key I44 adapted to engage a keyway I45 which extends some distance along the shaft H2. The worm I 36; worm wheel I31, and the bevel gears I89, III, MI, and I42 are so proportioned that '30 the cam shaft 58 will be rotated in a desired synchronism with the mechanism of the camera. When the casing 25 is moved leftwardly from the full line position in which it is shown in Fig. 2 to the position in which it is shown by dotted lines I46, so as to bring the camera lens 24 into alignment with the range finder or focusing attachment I41 thereof, the gear case II9 and the gear I42 therein slide leftwardly along the leftward portion II8 of the shaft II2 to the position indicated by dotted lines I48.

It is a further feature of the invention to provide means of adjustment whereby the angle of swing s, Fig. 3, of the refracting member 34 may be varied, thereby changing the degree of refraction of light rays passing from the object into the camera to a desired value. This result we accomplish, as best shown in Figs. '7, 12, and

' 13, by supporting the pivot means 83 so that it may be moved along the fulcrum lever 82. As shown in Figs. 11 and 12, the lever 82 has a slot I58 between side bars I 5| and I52. A square block I53 is disposed in the slot I58 and is adapted to be clamped in any desired position in the slot I50 by means of a clamping screw I54 which passes through a longitudinal channel I55 in the side bar I52, into threaded engagement at I56 with the block I53, as shown in Fig. 11. A pivot pin I51 projects vertically through an opening I58 in the block I53, and the ends thereof are supported by arms I59 and I6! which project laterally from a traveling block I62. The block I62 has a threaded opening I63, through which a lead screw I64 is threaded,- and in the lower part of the block I62 there is a slot I65 in which a guide bar I66 extends. The lead screw I64 projects longitudinally within the forward part of the chamber 56 and projects through a body I61 formed on a side wall I68 of the chamber 56. For rotation of the screw I64, a ,knob I69 is provided on the outer end thereof, and a locking screw I" provided with a knob I12 is located at thebody I61 where it is operative to clamp the screw I64 against rotation. As shown in Figs. 9, 10, 12, and 13, a temporary locking means I13 is provided for the lever 82 to tive to the lever 82.

1 I11 in the forward end III of the lever 82.

hold the same stationary while the traveling block I62 and the pivot means 83 are moved rela- This locking means I13 consists of a pin I14 which passw downwardly through an openingv I15 so positioned that the 5 lower end I16 of the pin I14 maybe moved downwardly into engagement with an opening As best shown in Fig. 10, this pin has an annular groove I18 which is engaged by a flat spring I19 10 which is secured by a screw I8I to the wall 5|. This spring I19 exerts a pressure tending to move the pin I14 downwardly, and the pin I14 is normally held in raised position by means of a small cotter pin I82 placed in the upper part 5 of the pin I14 in such position that the projecting ends thereof will rest upon abutments I83, but which may be lowered into a diametral slot I84 when the pin I14 is rotated through an angle of from the position in which it is shown in Fig. 10.

A change in the position of the pivot means 83 is accomplished as follows: The camera mechanism is operated so as to bring the lobe 66 or 61 into engagement with the follower 14 so that the lever 82 will be brought into an intermediate position as shown in Fig. 12. The pin I14 is then rotated to bring the cotter pin I82 into alignment with the slot I84, thereby dropping the pin I14 so that the lower end I16 thereof will engage the opening I 11 of the lever 82. A cover I85, Fig. 6, forming a part of the top 'wall of the chamber 56, is removed to provide access to the clamping screw I54, and this clamping screw I54 and also the clamping screw I1I are loosened, whereupon rotation of the lead screw I64 may be employed to cause movement of the traveling block I62 and the pivot means 83 in lengthwise direction relative to the lever 82, so that the block I53 of the pivot means 83 may be brought to a desired new position between the ends of the lever 82, thereby changing the fulcrum point of .the lever 82, with the result of a corresponding change in the swing of the retracting member 34. When the block I53 is brought into a desired new position of operation, the clamping screws I54 and HI may be retightened, whereupon the locking pin I14 may be lifted and rotated through an angle of substantially 90' so that 50 the engagement of the ends of the cotter pin I82 with the abutments I83 will hold this pin I14 in the raised position in which it is shown in Fig. 10.

We claim as our invention:

1. An attachment for a motion picture camera having a film moving mechanism for bringing the frames of a motion picture film consecutively into line with the optical axis of the lens of such camera, including: a support; means for securing said support to a camera. in a plane ahead of the lens of the camera; an optical flat refractory member; pivot means on said support supporting said refractory member in a position crossing said optical axis of said lens, said pivot means defining 'an axis of rotation for said refractory member disposed at an angle to said optical axis; a lever connected to said refractory member; a cam for swinging said lever rightwardly and leftwardly; means forming an operative connection between said cam and said lever whereby to so swing said lever; and drive means for said cam, said drive means having operative connection with said film moving mechanism of said camera and rotating said 75 aiaarac cam in timed relation to film in said camera.

2. An attachment for a motion picture camera having a film moving mechanism for bringing the frames of a motion picture film consecutively into line with the optical axis of the lens of such camera, including: a support; means for securing said support to a camera in a plane ahead of the lens or" the camera; an optical fiat refrac tory member; pivot means on said support supporting said refractory member in a position crossing said optical axis of saidlens, said pivot means defining an axis of rotation for said refractory member disposed at an angle to said optical axis; a lever connected to said refractory member; a cam for swinging said lever rightwardly and leftwardly; means forming an operative connection lsetween said cam and said lever whereby to so swing said lever, said connecting means including cooperating parts secured together in adjustable relation whereby the angle of swing of said lever may be varied; and drive means for said cam, said drive means having operative connection with said film moving mechanism of said camera and rotating said cam in timed relation to the movement of said film in said camera.

3. An attachment for a motion picture camera the movement of said tory member;

having a film moving mechanism for bringing the frames of a motion picture film consecutively into line with the optical axis of the of such camera, including: a support; means securing said support to a camera in a plane ahead of the lens of the camera; an optical flat refra tory member; pivot means on said support sup porting" said refractory member in a position crossing said optical axis of said lens, said pivot 'means defining an axis of rotation for said re iractory member disposed at an angle to said optical axis; a lever connected to said refraca cam for swinging said lever rightwardly and leftwardly; means forming an operative connection between said cam and said lever whereby to so swing said lever, said connecting means including co-operating parts secured together in adjustable relation whereby the angle of swing of said lever may be varied;

drive means for said cam, said drive means liar/ ing operative connection with said film moving mechanism 'of said camera and rotating said cam in timed relation to the movement of said film in said camera; and locking means operathig to hold said lever during the periods in is immovable.

HAROLD A. ADAMS.

amen LEliniRT.

CERTIFICATE OF CORRECTION.

Patent No. 2,11 .6,15}.

column; offset vvith relation;

HAROLD A. ADAMS, ET AL line 22, after the word "have" insert February 7, 19590 ppears in the printed specification correction as follows: Page 1, first images which are laterally and that the said Letters Patent should be read with this correctiontherein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 21st day of March, A.D. 19 9,

(Seal) Henry Van Arsdale Acting Commissioner of Patents. 

